1. Field of the Invention
The present invention relates to an image forming apparatus such as a printer, a copier, and a multifunction peripheral (MFP).
2. Related Art
Recently, image forming apparatuses (e.g., a printer, a copier, and a MFP) have been used as indispensable office machines in a company. At the same time, the image forming apparatuses have been widely used as household machines.
Some image forming apparatuses adopt a secondary transfer method. In the secondary transfer method, a visible image is formed with developer, and the visible image is transferred onto an intermediate transfer part. Then, the visible image on the intermediate transfer part is further transferred onto a recording medium (e.g., a sheet of paper).
It is required for the image forming apparatus adopting the secondary transfer method to determine accurately a position of the visible image on the intermediate transfer part for the purpose of accurately transferring the visible image onto a sheet of paper. Also, it is further required for a color-image forming apparatus adopting a method of forming a full-color image to adjust accurately a position of the visible image by overlapping various color visible images on the image transfer part.
In response to the above-mentioned demand, Japanese Patent Application Publication No. JP-A-2002-278203 discloses an apparatus for positioning a toner image based on a mark provided on an intermediate transfer belt (i.e., intermediate transfer part).
According to the Publication, when developer remains on the intermediate belt without being transferred onto a sheet of paper, a cleaning part is configured to remove it. However, it is impossible to remove completely the developer remaining on the intermediate belt. Therefore, developer will be gradually accumulated on the intermediate transfer belt as “grime.” A great deal of grime accumulated on the intermediate transfer belt negatively impacts image quality. In other words, accurate and beautiful printing will not be performed. In this case, it is judged that the intermediate transfer belt has come to the end of its lifespan and accordingly needs to be replaced.
Accordingly, aspects of the present invention have been created to solve the above-mentioned problems occurring in the conventional practice and to provide an image forming apparatus for prolonging lifespan of an intermediate transfer part by dispersing grime on the intermediate transfer part.